If on your exchange 2007 or exchange 2010 server you find you are getting complaints from users who are getting a lot of spam emails then you can enable exchanges bult in ant-spam filtering. This is not enabled out of the box for the full blown product, just SBS 2008 and sbs 2010. This is simply a case of running a powershell script. Follow the step by step guide below on how to enable microsoft exchange 2010 or 2007 anti-spam filtering. There is a video guide at the end of the article showing you how to do this.
To enable the anti spam options do the following.
1) first we need to run the exchange powershell management console…
2) We then need to go to the following directory.
C:\Program Files\Microsoft\Exchange Server\V14\Scripts
( Or where you exchange installed )
3) we then need to run the following command
4) once this is done run the exchange management console and under Hub transport you will see the anti spam agents are installed.